THE ALBUMIN EXCHANGE IN THE RABBIT EYE.

Abstract

AbstractRed cells labelled with Cr51 and albumin labelled with I131 were given i. v. to unanesthetized rabbits. Additional doses of I131‐albumin kept the plasma concentration of labelled albumin at a steady value. At different times after the first injection the animals were killed and the eyes dissected. The red cell contents of the choroid, the anterior uvea and the retina were the same at all time intervals, while the apparent volume of the plasma equivalent albumin space in the tissues increased with time. The results were analyzed in terms of intravascular and extravascular albumin compartments having the same concentration of I131‐albumin as plasma. The apparent volumes of the extravascular plasma albumin compartments were: in the choroid 112 μl per g tissue, in the anterior uvea 94 μl per g tissue and in the retina 4.8 μl per g tissue. The apparent turnover rates for the albumin solution in the extravascular albumin compartments were: in the choroid 0.0847 μl per min, in the anterior uvea 0.234 μl per min and in the retina 0.0075 μl per min. It was calculated that the albumin concentration in the tissue fluid of the choroid and in that of the anterior uvea as a whole is more than tenfold the albumin concentration in the aqueous humour and that the albumin drainage with the aqueous humour can account for less than 10 per cent of the albumin drainage from the eye.